More than 50,300 refugees have arrived in Kosovo and another 5,000 fled to southern Serbia since fighting intensified earlier this year in Macedonia.

NATO Secretary General George Robertson denounced the renewed fighting between Macedonian forces and ethnic Albanian rebels as "complete folly."

As government troops attacked Aracinovo on Friday, the NATO chief demanded that the "madness" stop.

Journalist Juliette Terzieff told CNN the fresh offensive was undermining the efforts of Western diplomats to avert all-out war.

A rebel leader known as Commander Hohxa said that three civilians were killed and many wounded, including one rebel fighter, in Friday's attack.

He accused the Macedonian army of breaking the truce and promised to fight back.

"I'm warning the government if they want war they're going to get one," he said by telephone from Aracinovo. "We will defend ourselves."

The army attacked positions in and around the village of Aracinovo -- from where rebels had threatened to launch their own assault on the capital, Skopje.

Macedonian gunships fired rockets at the village

The assault came 11 days into a fragile cease fire and as political leaders were attempting to inject some impetus into deadlocked peace talks.

Artillery set a four-story house in Aracinovo on fire, blanketing the eastern part of the village with heavy gray smoke.

Mi-24 helicopters swooped on the village, which is 10 km (six miles) from Skopje, firing repeatedly at the area.

The European Union and NATO are currently engaged in a cliffhanger bid to broker a deal to avert civil war.

"This help is being undermined and threatened by this unacceptable resort to violent action," Robertson added.

Macedonia said it had launched the assault to "eliminate" the Albanian National Liberation Army from Aracinovo, a village which is practically a suburb of Skopje.

Robertson urged Macedonian political leaders to "get serious about producing a political solution ... and to focus urgently on producing an agreement."

"This is no time for half measures on the political side or time-wasting posturing. The people need their leaders to immediately chart the way to a peaceful future," he said.

He said Macedonia was "on the brink of bloody civil war." Without directly blaming the Macedonian security forces for Friday's resumption of hostilities, Robertson said "the breach of two unilateral declarations of military restraint put in place is deeply regrettable."

European Union foreign ministers have invited the Macedonian government and party leaders to a meeting in Luxembourg on Monday at which they have said they expect to see a peace settlement in writing.

This would pave the way for a NATO force of 3,000-5,000 troops to collect the arms of the NLA forces, which would be surrendered voluntarily as part of a pact offering them amnesty.

But political negotiations have broken down over Albanian demands for a new constitution giving them a veto on all major decisions by the state -- a positions ethnic Macedonians say amounts to partition.